(a) Field of the Invention
The present invention relates generally to a heat dissipation device for computers, and more particularly to a convection type heat dissipation device that is adjustable with respect to a heat source so as to provide enhanced heat dissipation effects.
(b) Description of the Prior Art
As the processing speed of today's central processing units is quite high, when a central processing unit operates under a fully loaded state, its surface temperature may reach as high as over 100.degree. C.
Therefore, central processing units are generally equipped with cooling fans or coolers for dissipating the heat generated thereby during operation, so as to prevent the central processing unit from getting overheated, which may cause the system to become unstable or even break down.
According to the method of dissipating heat using cooling fans, the blades of the fan rotate to generate an air current which carries away with it the heat produced by the central processing unit. With conventional coolers, the cooler is fastened to the surface of the central processing unit and is made of material that may dissipate heat readily. The cooler is further provided with a plurality of blades or vanes so that it may help dissipate the heat of a larger area and effectively reduce the surface temperature of the central processing unit.
However, no matter whether cooling fans or coolers are used to help dissipate the surface heat of the central processing units, the heat dissipation efficiency is still not satisfactory. The major reasons are:
1. As the central processing unit is accommodated within an almost completely enclosed computer mainframe, the heat generated thereby cannot be continuously and effectively carried to the outside from the enclosed housing by utilizing the conventional heat dissipating devices as described above. The longer the period the central processing unit operates, the worse the effects of heat convection within the housing, resulting in low heat dissipation efficiency. PA0 2. In view of the present trend to compactize computers, the space available within the housing for accommodating the mother board will become smaller and smaller. Therefore, the dissipation of heat generated by the central processing unit becomes more a problem, and heat dissipation becomes more difficult with more compact systems. PA0 3. From the viewpoint of the present day technology development, if it is desired to raise the number of bytes processable by the central processing unit or to increase the processing speed, how to enable the central processing unit to dissipate its heat more speedily is a major concern.